1. Field of the Invention
This invention relates to a statically stable ballistic projectile. In particular, the statically stable projectile possesses fixed canards and thrusters that are located within the nose section of the projectile to control pitch and yaw. The projectile canards and thrusters react to a sensor guidance input or pre-programmed instructions.
2. Brief Description of the Related Art
Projectiles in weapon systems require aerodynamic stability and guidance control. Initially, basic guidance control included xe2x80x9cpoint-and-firexe2x80x9d weapons that possess no corrective flight after launch. As projectiles became capable of longer ranges, in-flight guidance became necessary. However, this produced several weight and stability problems.
One known maneuvering mechanism uses canards. Canards provide continuous correction capability and a reduction in static margin, but the necessary actuators for the canards pose packaging and power problems on projectiles. Other maneuvering mechanisms uses discrete thrusters, providing packaging advantages over the use of canards.
In view of the foregoing, there is a need for improvements in projectile guidance.
The present invention includes a guidance device for projectiles comprising at least two canards, the canards positioned on the nose of the projectile, at least one thruster positioned on the nose of the projectile cooperatively located to influence at least one of the canards and means for guidance that controls at least part of the interaction between the at least two canards and at least one thruster for directing the projectile in flight.
The present invention also includes a system for stabilizing a projectile comprising a projectile having a guidance device having at least two canards, the canards positioned on the nose of the projectile, at least one thruster positioned on the nose of the projectile cooperatively located to influence at least one of the canards and means for guidance that controls at least part of the interaction between the at least two canards and at least one thruster for directing the projectile in flight, wherein the center of gravity is forward of the center of pressure, and the center of gravity and the center of pressure are separated by a distance of from about 20% or less of the length of the projectile.
Additionally, the present invention includes a method for creating stabilized flight of a projectile, comprising the steps of providing a projectile having a guidance device with at least two canards, the canards positioned on the nose of the projectile, at least one thruster positioned on the nose of the projectile cooperatively located to influence at least one of the canards and means for guidance that controls at least part of the interaction between the at least two canards and at least one thruster for directing the projectile in flight, launching the projectile and controlling the flight of the projectile with the guidance device.
Static margin effects the stability of the projectile, and reductions in the static margin increase maneuverability. This reduced level of static margin is designed into the configuration of the projectile by either controlling the center of gravity position or varying the mass, i.e., size or number, of the fins on the projectile.
Other and further advantages of the present invention are set forth in the description and appended claims.